Greenhouse gases (“GHG”) are gases in an atmosphere that absorb and emit radiation within the thermal infrared range. The primary greenhouse gases in the Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, and ozone.
The 2010 United States federal budget proposes to support clean energy development with a 10-year investment of $15 billion per year, generated from the sale of GHG emissions credits. Under the proposed cap-and-trade program, all GHG emissions credits would be auctioned off, generating an estimated $78.7 billion in additional revenue in FY 2012, steadily increasing to $83 billion by FY 2019.
Emissions trading is a market-based approach used to control pollution by providing economic incentives for achieving reductions in the emissions of pollutants. Governing entities may establish a limit or cap on the amount of a pollutant that can be emitted. Such limit or cap may be applied, allocated, or sold to entities which have been identified as capable of producing emissions at a level which could be subject to the established limit or cap for said designated pollutants. These limits or caps may be applied, allocated, or sold to such emissions entities in the form of emissions permits which represent the right to emit or discharge a specific volume of a specified pollutant. Such emission producing entities are required to hold a number of permits (or credits) equivalent to their emissions. The total amount of permits (or credits) issued by the governing entity cannot exceed the cap; thus, limiting total emissions to that level. Emissions entities that need to increase their level of emissions must buy permits from those who require fewer permits. The transfer of permits is referred to as a trade. In effect, the buyer is paying a charge for polluting, while the seller is being rewarded for having reduced emissions.
The overall goal of an emissions trading plan is to minimize the cost of meeting a set emissions target. The cap is an enforceable limit on emissions that is usually lowered over time—aiming towards a national emissions reduction target. In other systems a portion of all traded credits must be retired, causing a net reduction in emissions each time a trade occurs. Thus, in theory, by limiting or capping polluting emissions the totality of pollution may be decreased. Moreover, those who can reduce emissions most cheaply will do so, achieving pollution reduction at the lowest cost to society.
There are active trading programs in several air pollutants. For GHG the largest is the European Union Emission Trading Scheme. In the United States there is a national market to reduce acid rain and several regional markets in nitrogen oxides. In 2003, New York State proposed and attained commitments from nine Northeast states to form a cap-and-trade carbon dioxide emissions program for power generators, called the Regional Greenhouse Gas Initiative. This program launched on Jan. 1, 2009 with the aim to reduce the carbon “budget” of each state's electricity generation sector to 10% below their 2009 allowances by 2018. Also in 2003, U.S. corporations were able to trade CO2 emission allowances on the Chicago Climate Exchange under a voluntary scheme. In August 2007, the Exchange announced a mechanism to create emission offsets for projects within the United States that cleanly destroy ozone-depleting substances.
Since February 2007, seven U.S. states and four Canadian provinces have joined together to create the Western Climate Initiative, a regional GHG emissions trading system. July 2010, a meeting took place to further outlined the cap-and-trade system which if accepted would curb GHG emissions by January 2012.
In 2006, the California Legislature passed the California Global Warming Solutions Act, AB-32. Project based offsets have been suggested for five main project types. A carbon project would create offsets by showing that it has reduced carbon dioxide and equivalent gases. The project types include: building energy, landfill gas capture, forestry, and manure management.
According to Food and Agriculture Organization statistics, ruminant livestock-derived methane has been estimated at 18% of the total global GHG emissions on a carbon dioxide equivalency basis. In addition, global protein consumption more than doubled since 1970 and is projected to double again by 2050. Ruminant-derived methane is produced during digestion (fermentation) of feed and fodder through microbial fermentation within the rumen. Ruminant methane levels are attributable to the rate, efficiency, and completeness of carbohydrate and protein conversion from feedstuffs into volatile fatty acids (“VFAs”). The molar percentage and composition of ruminal VFAs produced during fermentation influence the production of methane. Acetate and butyrate promote methane production while propionate formation is considered a competitive pathway for hydrogen use in the rumen.
There is an inverse relationship between fermentation efficiency and methane production within the rumen. Metabolic energy loss during rumen digestion can be attributed to heat loss during fermentation, as well as the production of ammonia and methane gas. Methane reduction within the rumen not only improves GHG emissions but is attributable to increased energy conversion and subsequent enhanced animal productivity. These benefits are of key interest to farmers and producers.
Feed (diet) and feeding strategies have demonstrated significant influence on fermentation products and energy production within ruminant animals. Rumen bypass protein products are an exceptional example of how nutritional manipulation can benefit animal productivity. Methane reducing feed additives, many of which are plant-based, however, have shown limited holistic success, or have demonstrated adverse trade-offs that have precluded their widespread practical application. These negative effects include reduced feed intake and protein synthesis, both of which can limit optimal growth and development. Natural feed additives which could improve dry matter digestion and reduce methane production would represent an appealing solution for reducing livestock-derived GHG while contributing to optimal animal nutrition. Thus, the natural feed additives described herein may allow farmers and producers to maximize their food commodity production, benefit from emissions trading programs, comply with greenhouse gas emission mandates, regulations, and contribute to a better global environment.